- 學位論文
Synthesis, Crystal Structures and Properties of Metal-Organic Frameworks with 4,4’,4”-s-triazine-2,4,6-triyltribenzoate, and 2,2’,2”-s-triazine-1,3,5-triyl-tri-o-aminobenzoate as Linkers
Synthesis, Crystal Structures and Properties of Metal-Organic Frameworks with 4,4’,4”-s-triazine-2,4,6-triyltribenzoate, and 2,2’,2”-s-triazine-1,3,5-triyl-tri-o-aminobenzoate as Linkers
摘要
本篇論文以合成與性質探討一系列配位化合物，分別利用兩種配位基4,4’,4”-s-triazine-2,4,6-triyltribenzoate (p-TATB)、2,2’,2”- s-triazine-1,3,5-triyltri-o-aminobenzoate (o-TATAB)，與二價及三價金屬進行合成反應，最後可以得到晶體化合物為[(CH3)2NH2]3[Ga3(pTATB)4]•22DMF•7H2O (1), [Cu3(oTATAB)2(H2O)3]•10DMA•3H2O (2) and [Ln4Na2(oTATAB)4(DMA)12](NO3)X (Ln= La(3a), Ce(3b), Nd(3c); X=Cl、Ln=La(3d); X=I). X光單晶繞射(single-crystal X-ray diffraction)顯示1為二重穿插的三維結構，使用PLATON軟體計算除去溶劑後的孔洞率為70.2%，但經溶劑交換除去DMF後並無法保持原本的結晶相；化合物2其結構以雙核銅金屬為中心，與四組羧基橋接形成常見的水車狀(paddlewheel)二級建構單元(secondary building unit，SBU)，孔洞率為53.5%，經四氫呋喃、乙腈溶劑交換後能保有原本的相，而溶劑分子離去後變成非結晶相，若再置入孔洞當中可以恢復，此晶體結構較為彈性可進行晶相到非晶相的轉換(reversible crystal to amorphous transformation)；(3a)~(3d)為一系列相等結構，皆是屬於二重穿插的三維架構，金屬中心是鑭系元素為九配位，經計算後孔洞率達51%，但經由加熱實驗後皆呈現非結晶相，此結構與p-TATAB, m-TATAB配基所合成之鑭系晶體類似，但o-TATAB配基結構是透過額外添加鈉離子與羧基間弱作用力穩定二重骨架，與先前結構以分子間氫鍵作用力穩定二重骨架略有不同。
關鍵字
無資料並列摘要
Here we report the synthesis and characterization of a series of metal-organic frameworks (MOFs), resulted from the self-assembly of metal ions and entitled ligands, 4,4’,4”-s-triazine-2,4,6-triyltribenzoate (pTATB) and 2,2’,2”-s-triazine-1,3,5-triyl-tri-o-aminobenzoate (oTATAB) : [(CH3)2NH2]3[Ga3(pTATB)4]•22DMF•7H2O (1), [Cu3(oTATAB)2(H2O)3]•10DMA•3H2O (2) and [Ln4Na2(oTATAB)4(DMA)12](NO3)X (Ln= La(3a), Ce(3b), Nd(3c); X=Cl、Ln=La(3d); X=I). Single-crystal X-ray diffraction studies indicate 1 has two identical interwoven 3D networks with solvent-accessible volume of 70.3% calculated using PLATON. Compound 2 crystallizes in cubic space group Pa-3. In its structure, two copper atoms are bridged by four carboxylates to form the well-known paddlewheel secondary building unit with axial aqua ligands. The framework of 2 remains intact after solvent-exchange by THF and ACN. Reversible crystal to amorphous transformation has also been observed in 2. In addition, we also synthesized four 3D isostructures, [Ln4Na2(oTATAB)4(DMA)12](NO3)X (Ln= La(3a), Ce(3b), Nd(3c); X=Cl、Ln=La(3d); X=I). The solvent accessible free volumes of (3a) to (3d), calculated by PLATON, are approximately 51% of the crystal volume. The structure of (3a) to (3d), appear to collapse into amorphous phases upon the removal of solvent molecules were studied by thermal analyses and powder X-ray diffraction. This structure is similar to {[Ln2(pTATAB)2(H2O)(DMA)3]•xH2O}n and {[Ln2(mTATAB)(DMA)3]}n, but its structure has to add the sodium ions . And the sodium atom and six carboxylates of the framework have interaction to stabilize two identical interwoven 3D networks.